lack vs tightness

lack and tightness both are nouns.

Word	Noun	Adjective	Verb	Adverb
lack	Yes	No	Yes	No
tightness	Yes	No	No	No

As nouns, tightness is a hyponym of lack; that is, tightness is a word with a more specific, narrower meaning than lack:

Other hyponyms of lack include absence, dearth, famine, shortage, deficit, mineral deficiency, shortness, stringency.

lack (noun)	tightness (noun)
the state of needing something that is absent or unavailable	lack of movement or room for movement
	extreme stinginess
	the spatial property of being crowded together
	a tight feeling in some part of the body
	a state occasioned by scarcity of money and a shortage of credit

lack (verb)	tightness (verb)
be without
To be insufficiently prepared